Ski binding

ABSTRACT

A ski binding has a pair of levers including boot holding jaws, pivotally mounted for movement of the jaws together and apart, and a spring urging the levers to bring the jaws together to a boot-engaging position. The force of the spring is transmitted to the levers by an intermediary piece having a central plane face which bears against projecting parts of the levers in said bootengaging position. The central plane face of the piece is extended by two lateral faces inclined towards the direction of the spring, and against which a respective part of a lever bears when it is moved apart from the other jaw by the application of a lateral force.

United States Patent Sentou Aug. 5, 1975 1 SKI BINDING [75] Inventor: Bernard Sentou, Cluses, France f 'r' Bhx ASSISIGH! ExammerJesus D. Sotelo i 1 Assigneei Mitdlell France Attorney, Agent, or FirmRbert E. Burns; [22} Filed: June 1973 Emmanuel J. Lobato; Bruce L. Adams 1 l pp 373,266 1571 ABSTRACT A ski binding has a pair of levers including boot hold Foreign Application Priority Data ing jaws, pivotally mounted for movement of the jaws June 29, 1972 France 72239:? ogether and 3pm, and a Spring urging the levels to bring the jaws together to a boot-engaging position. 52 us. c1 280/1 1.35 T The of the Spring is transmitted to levers by [51] Int. Cl A63c 9/00 an intermediary piece having a Central plane face 8] Field ofSearch ..2s0/11.35 R, 11.35 A. which bears against P j g parts of h levers in 280/1135 B 35 D34/l4 D said bootengaging position. The central plane face of the piece is extended by two lateral faces inclined to- [56] References Cited wards the direction of the spring, and against which a UNITED STATES PATENTS respective part of a lever bears when it is moved apart from the other jaw by the application of a lateral 3.380.750 4/1968 Salomon 280/1135 T form 3.463.503 8/1969 5 T 3.572.738 3/l97l Martin 280M T 4 Claims, 5 Drawing Figures SK] BINDING The present invention relates to safety ski bindings.

A known type of safety ski binding for freeing a boot subjected to a given lateral force comprises two levers pivotally mounted about vertical axes, one end of each lever forming a jaw for holding a boot sole, elastic means constantly urging the second ends of the levers to hold the two jaws in a closed boot-holding position, an intermediary piece movable parallel to the axis of compression of the eleastic means being interposed between the elastic means and the second ends of the levers.

Numerous bindings with a release system of the type mentioned above are known. An object of the invention is to provide a new binding of this type which is of simple and economic construction and is sure in operation.

Accordingly, a safety ski binding according to the invention is characterized in that the intermediary piece has a central part having a plane face opposite a face against which the elastic means bears, disposed substantially perpendicular to the axis of compression of the elastic means and on which the second ends of the levers bear when the jaws are in said closed position, and two faces adjacent to said central part and inclined towards the elastic means, the second end of a lever bearing on a respective one of said inclined faces when the respective jaw is opened by a certain angle.

Since this binding involves very simple and hence low-cost component parts, the manufacturing advan tage of the binding can be easily appreciated.

Embodiments of the invention will now be fully described, by way of example, with reference to the accompanying schematic drawings, in which:

FIG. 1 is a diagrammatic plan view ofa first embodiment of binding in its normal use position, locking a boot in place;

FIG. 2 shows the same binding in a position corresponding to freeing of the boot by the exertion of a given lateral force;

FIG. 3 is a perspective view of an intermediary piece of the first embodiment;

FIG. 4 is a simplified plan view, partially in cross section, of a second embodiment of binding; and

FIG. 5 is a view similar to FIG. 4 of a third embodi ment.

With reference to FIG. 1, the binding shown comprises two lateral levers 1,2 which are pivotally mounted about respective axes 3,4 fixed in parallel spaced-apart relation perpendicular to a base plate, not shown, adapted to be secured on the upper surface of a ski. The principal or first arms of levers 1,2 terminate at their free ends by jaws 5 and 6 which are shaped so as to embrace the front end of the sole of a boot 7 to be held. The levers 1,2 also include inwardly-directed second arms 8 and 9 the adjacent free ends of which are pushed towards the right of the Figure by a compression spring 10, the action of this spring being trans mitted by means of a mobile intermediary piece 11.

In this embodiment, the piece 11, which is best seen in FIG. 3, takes the form of a plate bent into three planar sections, a central section 18, having a rear face against which an end of the spring 10 acts and a front face against which the ends of arms 8 and 9 are applied as shown in FIG. 1, and two lateral sections 12 and 13 each inclined at an obtuse angle a with the rear face of central section 18. These inclined lateral sections 12,13, instead of being planar, alternatively could be convex or concave, and the piece 11 could be of overall trapezoidal shape rather than rectangular as shown. The piece 11 could also be a surface of revolution i.e. a disc or washer, with a single frusto-conical or other inclined lateral surface.

The other end, 14, of spring 10 opposite to the end applied against piece 11 bears against a schematically indicated stationary plane of the binding frame.

The intermediary piece I] is free to move in the longitudinal direction of spring 10 inside a housing 15 of the binding frame, the edges of this housing 15 serving to guide the piece 11 for sliding movement along housing 15 to the exclusion of any rotation about the axis of spring 10. The piece 11 is, however. free to tilt slightly about an axis parallel to axes 3 and 4.

A pair of fixed stop members 16 and 17 are provided for limiting the movement of arms 8 and 9 under the action of spring 10.

Operation of the binding is as follows. The force of spring 10 is transmitted by the piece 11 to the ends of arms 9 and 10 which are applied against the stop members 16 and 17. The arms 1 and 2 and their jaws 5 and 6 are thus held towards one another in a stable and well defined position in which the jaws 5 and 6 can grip the sole of boot 7, as shown, to hold the boot in place.

If, during use, a certain lateral force represented by arrow F is exerted on the boot 7, the binding moves to the position shown in FIG. 2, in which the jaw 6 has been displaced in the direction of arrow F. The movement of jaw 6 and its arm 2 by pivoting about axis 4 corresponds to a sliding of the end of arm 9 outwardly over the central section 18 of piece 11 and tending to compress the spring 10. For a certain limiting applied force, the end of arm 9 reaches the joint between sections 18 and 13, and the end of arm 9 continues to slide outwardly over section 13. This change of slope corresponds to an abrupt reduction (but not cancellation) of the force with which jaw 6 tends to inwardly hold the sole of boot 7; this force still has a sufficient value to automatically return the jaw 6 to its initial position after complete removal of the boot 7.

During this releasing operation, the piece 11 becomes inclined, as shown in FIG. 2, so that from the moment when the end of arm 9 contacts the face of section 13, this section 13 is oriented almost tangential to the trajectory of the end of arm 9, whereby the force of compression of spring 10 remains approximately constant while the end of arm 9 coacts with section 13. The boot 7 can thus continue its movement in the direction of arrow F without encountering any additional resistance, and can thus be freed. During the entire release operation described, the arm 8 of lever 1 remains stationary, applied against its stop member 16.

The binding shown in FIG. 4 comprises a pair of lateral levers 21,22 pivotally mounted about respective parallel, spaced-apart shafts 23,24 which are fixed perpendicular to a base plate, not shown. The free ends of the main arms of levers 21,22 form jaws 25,26, respectively. The levers 21,22 also include short inwardly projecting arms 28,29 having inner plane faces 28',29' perpendicular to the main arms of the levers. The arms 28,29 are permanently urged by a compression spring 30 the force of which is transmitted by an intermediary mobile piece 31 having the cross-sectional shape shown. The outer faces of arms 28,29 cooperate with a stationary stop member 36 secured on the binding frame, which enables limitation of the pivoting of the levers under action of spring 30 in the clockwise direction for lever 22 and in the counter-clockwise direction for lever 21. in the normal or rest position of the binding, not shown. faces 28', 29' of arms 28,29 are both applied against a central plane face 38 of piece 31. This central plane face 38 is extended laterally by two adja cent inclined faces 32,33, which are inclined generally in the direction of spring 30, for the purpose of enabling release in a similar manner to that previously described. The piece 31 and spring 30 are guided by a fixed rod 39 in the form of the shank of a screw with a head 40, this rod or shank passing through a central aperture in the stop member 36 and a central bore in piece 31. The piece 31 is fitted about the rod 39 with a play allowing a limited tilting of the piece 31, as shown, during the boot-releasing operation. A nut 34, which is prevented from turning by engagement with a part of the binding frame (not shown), is screwed on the threaded end of rod 39 and serves as a stop for the other end of spring 30.

In the event of a force, represented by arrow F, being applied to one of the levers, 21 for example, the face 28' of arm 28 is pushed against the plane face 38 of piece 31, which presses the piece 31 against the action of spring 30 and causes it to tilt slightly about rod 39. lf the applied force has a certain value, the edge of face 28 continues to slide outwardly over face 38 until it comes to act on the inclined face 32, as shown in FIG. 4, whereupon a boot held by jaw 25 can be freed, as previously described. Since the piece 31 has a radial play about the guide rod 39, the arm 29 is maintained against the stop member 36 by the action of plane face 38 against face 29', and the arm 22 and its jaw 26, which are not subjected to any lateral force. remain in the initial position.

In the embodiment shown in FIG. 5, a pair of lateral levers 41,42 pivotally mounted about shafts 43,44 have jaws 45,46 at the free ends of main arms thereof. The levers also have short arms 48,49 projecting inwardly from the respective shafts 43,44 and which carry fitted parts 48,49' of triangular cross-section (in a plane per pendicular to the shafts 43,44) serving as points of Contact of the levers 41,42 with an intermediary mobile piece 51. As in the previous embodiments, the ends 48,49 of the levers are permanently urged by a spring 50, through the piece 51, towards a stationary stop 56 secured on the binding frame. The piece 51 has a central plane face 58 extended by two lateral faces 52,53 which are inclined towards the spring 50, these faces 52,53 being slightly concave in this embodiment. The piece 51 and spring 50 are guided by the shank of a screw 59 which passes, without play, through a bore in piece 51. A nut 54, held against rotation by cooperation with a part of the binding frame (not shown), is screwed on the threaded end of screw 59 and forms a support for the other end of spring 50.

Operation of this binding is as follows. In the normal, boot-holding position, not shown, the central plane face 58 of piece 51 bear against the lower" face or base of the triangular parts 48,49. If a lateral force represented by arrow F is applied to one of the levers, for example 41, as shown, the end 48 of lever 41 is made to bear by the base of triangular part 48' against the plane face 58 of piece 51, which causes an axial displacement of piece 51, without any tilting along the shaft of screw 59 and a consequent compression of spring 50. Lever 42 does not move and its triangular piece 49' is thus slightly separated from the plane face 58 of piece 51. For a certain value of the lateral force, the triangular piece 48' leaves the central plane face 58 and its inner edge slides over the inclined face 52 without further compressing spring 50, i.e. without displacing the piece 51. This can be achieved by making the inclined concave faces 52,53 approximately concentric to the shafts 43,44 (when the piece 51 is in the appropriate position) so that when the edge of triangular piece 48' or 49' slides over the respective surface 52,53, the piece 51 is not pushed against the action of the spring 50. Therefore, to achieve movement, only a frictional force between the said edge and the surface of piece 51 has to be overcome.

As a variation, other shapes and dimensions of the operative faces of the intermediary piece can be previewed. Similarly, the ends of arms 8,9; 28,29 or 48,49 could be provided with rolling means such as balls, rollers or pulleys so as to replace the sliding friction against the faces 12,13; 32,33; or 52,53 by a rolling friction.

Regulation of the bindings, eg. to provide a suitable jaw separation, can be achieved simply by providing means for adjusting the position of the stop members 16,17; 36; and 56 respectively.

The invention is applicable to many types of safety ski bindings, particularly toe bindings, whenever it is desired to provide a maximum security against the danger of excessive lateral forces, by simple and economic means which are suitable for providing easy and reliable regulation.

I claim: 1. A safety ski binding, comprising; two levers, each having first and second ends; two jaw means, each provided on the first end of one of said levers, for jointly holding a boot sole and for lateral movement to release the boot sole in response to a lateral force acting on the boot;

spring means for elastically urging the second ends of both levers in a longitudinal direction for the holding of the boot sole by said jaw means;

an intermediate plate between the spring means and the second ends of the levers, said plate having a central face transverse of said longitudinal direction, having two lateral faces contiguous with and rearwardly inclined to said central face and having rear surfaces of said central and lateral faces which hold said plate substantially centered on said spring means; and

means for so mounting said levers, relative to said intermediate plate, that (a) the second ends of both levers bear on said transverse face when the jaw means hold the boot sole, (b) the second end of one lever moves outwardly over said transverse face of said plate held substantially centered on said spring means, towards the respective inclined face, to relatively strongly compress said spring means in response to an initial lateral movement of the respective jaw means while the jaw means continue to hold the boot sole, and (c) the second end of said one lever moves outwardly onto the respective inclined face to at most relatively weakly further compress said spring means in response to further lateral movement of the respective jaw means to release the boot sole.

6 means and for tipping movement relative to said axis. 4. Binding according to claim 1, including fixed stop means for limiting pivoting movement of said levers,

under the action of said elastic means. 

1. A safety ski binding, comprising; two levers, each having first and second ends; two jaw means, each provided on the first end of one of said levers, for jointly holding a boot sole and for lateral movement to release the boot sole in response to a lateral force acting on the boot; spring means for elastically urging the second ends of both levers in a longitudinal direction for the holding of the boot sole by said jaw means; an intermediate plate between the spring means and the second ends of the levers, said plate having a central face transverse of said longitudinal direction, having two lateral faces contiguous with and rearwardly inclined to said central face and having rear surfaces of said central and lateral faces which hold said plate substantially centered on said spring means; and means for so mounting said levers, relative to said intermediate plate, that (a) the second ends of both levers bear on said transverse face when the jaw means hold the boot sole, (b) the second end of one lever moves outwardly over said transverse face of said plate held substantially centered on said spring means, towards the respective inclined face, to relatively strongly compress said spring means in response to an initial lateral movement of the respective jaw means while the jaw means continue to hold the boot sole, and (c) the second end of said one lever moves outwardly onto the respective inclined face to at most relatively weakly further compress said spring means in response to further lateral movement of the respective jaw means to release the boot sole.
 2. Binding according to claim 1, in which each of said two inclined faces of the intermediary piece is planar and inclined to said plane face by an obtuse angle.
 3. Binding according to claim 1, including means for mounting the intermediary piece for movement longitudinally of the axis of compression of said elastic means and for tipping movement relative to said axis.
 4. Binding according to claim 1, including fixed stop means for limiting pivoting movement of said levers, under the action of said elastic means. 